In Germany, temporary agency work has strongly increased over the last decade. It is used as a short-term cover in case of personnel shortages, to accommodate seasonal fluctuations as well as to hedge against market volatilities. At the same time, contracts for work and services appear to have become a standard contractual basis of employment, particularly in the manufacturing industries. This constitutes major challenges for the institutions representing the interests of workers in the field of industrial relations: Both trade unions and works councils inside the hirers' businesses must face the problem of representing the interests of a more heterogeneous group of workers. In this context, this paper examines the strategic responses of the German trade union IG Metall to the in-crease of contracts for work and services and temporary agency work. It also analyses how the works councils within the hirers' businesses can theoretically implement the IG Metall claims and strategies. It is argued that the IG Metall sets different priorities within its strategies. Furthermore, it becomes clear that works councils only have very limited possibilities in order to support the trade unions' strategies due to the existing legal framework. This particularly concerns dealing with contracts for work and services.